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Webinar Q&A SPC charts

Does the model health system include mental health and community services?
Yes – just go to the views of trusts that provide mental health services. 

Are there any metrics specific to cancer?           
Yes, there are metrics for Cancer and Rightcare. If you can’t find a particular metric, you can use the search facility.

Are you going to look to include primary care data? 
Yes, when we get access to the data.

Are metrics such as days off sick for staff available?
Take a look in our People section - which we have recently aligned to the areas in the People plan. There are also staffing metrics underneath the different clinical specialties.

Will sustainability metrics be included?
Yes, we have Greener NHS metrics in the estates and facilities section

I’m not seeing the new home page
If you’re seeing a page with a blue banner you are in provider view. You’ll need to change to system view – more here.     

What time period is the data pulled from?       
It varies from metric to metric, depending on the data source. Each metric has an 'understand the data' section at the bottom of the page. This includes information on the data source, the date it was published, as well as information on how the metric was calculated, to help you replicate it from your local data if you want. 

I can see some data is outdated on Model Hospital eg 2020. Is there a timetable for updating?
Some data is only published annually, eg Patient Level Information and Costing System (PLICS). We aim to update data when it becomes available to us. However, due to Covid, some areas are lagging, which we are working on.

Does the data largely rely on systems recording the data somewhere at the the right time and accurately?
Yes. Wherever possible we use national data sources, eg Hospital Episode Statistics (HES),  Secondary Uses Service (SUS) and Electronic Staff Record (ESR).

How do you ensure comparability of data from organisations/systems?
By user peers or standardised metrics, e.g. the Weighted Activity Unit (WAU).
More information about the WAU.

Recently, our IG (Information Governance) has enquired how the Centre (NHSEI, NHS Digital) have sought to ensure the data protection rules/legislations are adhered to whilst utilising the patient level information. Are you able to point to me to any relevant links/documents that could satisfy our IG that data protection rules are adhered to once data is submitted to national tools?     Email the  and we can send you details of our IG policies.

We are struggling to reconcile the financials in model hospital to our NCC submission.
Contact  for more help.       

Do you use data from NHS Benchmarking Network?
Not any more, we used to, but collect our own now.

How do you select SPC Chart view?
Top right of charts, but it only appears when there are enough data points.

Should process limits not be recalculated when a significant external event (eg Covid) occurs?
Yes - there are a set of circumstances that need to be in place before process limits are recalculated,  We cover that in our training.

Do you have a tool to produce SPC charts?       
We have a wide range of tools available to you which are available here Tools - Making Data Count - FutureNHS Collaboration Platform

Can SPC only be used with data in percentages?
No – the majority of data sets can be used for SPC charts.  More information is available in our training sessions.

Is there use of different types of SPC chart? Take an indicator such as incidents per 1000 bed days, the 1000 bed days is variable as is the incidents - do you use u or still use xbar?
We promote the use of XmR charts for a range of reasons (exception is only rare events) - there are restrictions about the other chart types in terms of data distribution (which most people aren't aware of) and which invalidate the other charts potentially.  Also XmR charts can deal with virtually all data types, are easy to produce and are easily understood.

Are the upper and lower limits calculated using standard deviation?
The process limits must be calculated using 3 sigma.  This is different to standard deviation which must not be used.  A short video explaining the differences is here Does it matter how you calculate process limits? - YouTube

How reliable are control limits if looking at monthly data over the past few years, thinking specifically about the impact of COVID and the fact we are working under ever changing circumstances?           
SPC enables us to understand the impact of covid and the recovery from it.  If you want to learn more about how to best deal with process limits over the covid period email

What is the point of the grey dotted lines on the 62-day waits chart? Especially the one over 100%?
The grey dotted lines are the process limits which describe the range of natural variation.  Process limits can go above 100%.  We cover this topic in our step 4 training session.

Why do you need the upper and lower limit? The problems are obvious without them.
Process limits enable us to understand the range of variation and the capability of a measure to meet a target.             

Is there a way of changing the date range on the SPC charts on the MHS?
Not at present. 

Can the time periods be selected to see where change has been made through action plans?
Not at present.

Sam - on the example you showed there were lots of dots in a downward trend but still blue ('special cause variation improving') until they crossed the line and became orange. Will there be colour coding for shifts/trends as well?             
The colour convention is already used for all 4 rules applied to the data (astronomical point, 2 out of 3 close to the process limits, shift and trend).

For SPC Charts in the NHS. Are SPC charts one dimensional only? Or are we able to input more then one variable to see the correlation of different dimensions on a single outcome?       
Only one measure must be plotted on a SPC chart.  For multiple measures you can use our multi tool 02 XmR Chart 12 Multi v18.0 - Making Data Count - FutureNHS Collaboration Platform

Sam, I'm interested to know your thoughts on people using run charts when they are fairly new to looking at data/ improvement. Not as robust as an SPC but do you think they're still valuable?           
My experience is that often people have used run charts as they have believed that SPC is too complicated or that there has been a cost to purchasing SPC software.  We provide free software and teach SPC in a simple way so these have not been problems.  I would only recommend using a run chart if there are not enough data points for SPC.

Can we use SPC for equality and inclusion data?
SPC can be used for most data sets.

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